neo-go/pkg/rpc/client.go
2019-10-22 17:56:03 +03:00

196 lines
4.2 KiB
Go

package rpc
import (
"bytes"
"context"
"encoding/json"
"fmt"
"net"
"net/http"
"net/url"
"sync"
"time"
"github.com/CityOfZion/neo-go/pkg/crypto/keys"
"github.com/pkg/errors"
)
var (
defaultDialTimeout = 4 * time.Second
defaultRequestTimeout = 4 * time.Second
defaultClientVersion = "2.0"
)
// Client represents the middleman for executing JSON RPC calls
// to remote NEO RPC nodes.
type Client struct {
// The underlying http client. It's never a good practice to use
// the http.DefaultClient, therefore we will role our own.
cliMu *sync.Mutex
cli *http.Client
endpoint *url.URL
ctx context.Context
version string
wifMu *sync.Mutex
wif *keys.WIF
balancerMu *sync.Mutex
balancer BalanceGetter
}
// ClientOptions defines options for the RPC client.
// All Values are optional. If any duration is not specified
// a default of 3 seconds will be used.
type ClientOptions struct {
Cert string
Key string
CACert string
DialTimeout time.Duration
Client *http.Client
// Version is the version of the client that will be send
// along with the request body. If no version is specified
// the default version (currently 2.0) will be used.
Version string
}
// NewClient returns a new Client ready to use.
func NewClient(ctx context.Context, endpoint string, opts ClientOptions) (*Client, error) {
url, err := url.Parse(endpoint)
if err != nil {
return nil, err
}
if opts.Version == "" {
opts.Version = defaultClientVersion
}
if opts.Client == nil {
opts.Client = &http.Client{
Transport: &http.Transport{
DialContext: (&net.Dialer{
Timeout: opts.DialTimeout,
}).DialContext,
},
}
}
// TODO(@antdm): Enable SSL.
if opts.Cert != "" && opts.Key != "" {
}
if opts.Client.Timeout == 0 {
opts.Client.Timeout = defaultRequestTimeout
}
return &Client{
ctx: ctx,
cli: opts.Client,
cliMu: new(sync.Mutex),
balancerMu: new(sync.Mutex),
wifMu: new(sync.Mutex),
endpoint: url,
version: opts.Version,
}, nil
}
// WIF returns WIF structure associated with the client.
func (c *Client) WIF() keys.WIF {
c.wifMu.Lock()
defer c.wifMu.Unlock()
return keys.WIF{
Version: c.wif.Version,
Compressed: c.wif.Compressed,
PrivateKey: c.wif.PrivateKey,
S: c.wif.S,
}
}
// SetWIF decodes given WIF and adds some wallet
// data to client. Useful for RPC calls that require an open wallet.
func (c *Client) SetWIF(wif string) error {
c.wifMu.Lock()
defer c.wifMu.Unlock()
decodedWif, err := keys.WIFDecode(wif, 0x00)
if err != nil {
return errors.Wrap(err, "Failed to decode WIF; failed to add WIF to client ")
}
c.wif = decodedWif
return nil
}
// Balancer is a getter for balance field.
func (c *Client) Balancer() BalanceGetter {
c.balancerMu.Lock()
defer c.balancerMu.Unlock()
return c.balancer
}
// SetBalancer is a setter for balance field.
func (c *Client) SetBalancer(b BalanceGetter) {
c.balancerMu.Lock()
defer c.balancerMu.Unlock()
if b != nil {
c.balancer = b
}
}
// Client is a getter for client field.
func (c *Client) Client() *http.Client {
c.cliMu.Lock()
defer c.cliMu.Unlock()
return c.cli
}
// SetClient is a setter for client field.
func (c *Client) SetClient(cli *http.Client) {
c.cliMu.Lock()
defer c.cliMu.Unlock()
if cli != nil {
c.cli = cli
}
}
func (c *Client) performRequest(method string, p params, v interface{}) error {
var (
r = request{
JSONRPC: c.version,
Method: method,
Params: p.values,
ID: 1,
}
buf = new(bytes.Buffer)
)
if err := json.NewEncoder(buf).Encode(r); err != nil {
return err
}
req, err := http.NewRequest("POST", c.endpoint.String(), buf)
if err != nil {
return err
}
resp, err := c.Client().Do(req)
if err != nil {
return err
}
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
return fmt.Errorf("remote responded with a non 200 response: %d", resp.StatusCode)
}
return json.NewDecoder(resp.Body).Decode(v)
}
// Ping attempts to create a connection to the endpoint.
// and returns an error if there is one.
func (c *Client) Ping() error {
conn, err := net.DialTimeout("tcp", c.endpoint.Host, defaultDialTimeout)
if err != nil {
return err
}
_ = conn.Close()
return nil
}